2007 Jeg's Engine Masters Challenge - Dyno-Mania!

The 2007 Jeg's Engine Masters Challenge was the forum for the recent shootout of factory-based musclecar engines, where the country's top builders duked it out for $192,000 in contingency prize money. With that kind of cash on the line, guys were going to put their best foot forward and employ every legal trick in the book.

In past years, we based the JEMC on a cubic inch limit, but that was no fun for builders, and it really didn't put things into perspective for readers more familiar with 305 Chevys, 318 Mopars, and 351 Fords. Average guy stuff. The rules for 2007 were simply to build a pump-gas musclecar engine between 302 ci and 500 ci, using the original OEM bore and stroke dimensions, plus a small margin for overbore and journal cleanup. Compression ratio was limited to 10.5:1. Components had to be commonly available aftermarket heads, intake, carb, and block, with full compatibility to the OEM components for the model year of engine built. For fun, we threw in a flat-tappet hydraulic camshaft rule because that presented a realistic limitation that the regular gearheads can emulate.

The qualifying scores were computed by taking (from three pulls) the average corrected torque and average corrected horsepower between 2,500 and 6,500 rpm, adding them together, multiplying by 1,000, then dividing by the claimed cubic inches. The score would then reflect the relative efficiency per cubic inch of each engine, thus leveling the playing field and removing the advantage of larger displacement motors.

What follows is the breakdown of each engine in competition, its qualifying score, OEM engine size, claimed displacement, and the best dyno sheet from the three pulls made during official qualifying. We've also included the important engine specs for your reference. Yes, we know there are gaping holes in the selection of engines (where's the 426 Hemi, the Mopar big-block 383 and 440 Wedge, the 302 Windsor, and the Boss 429-to name a few?). But when push came to shove, these were the engines our competitors elected to build, based on their perceived competitive advantage. Let's crank up the dyno!